Apparatus for incinerating material



R. GRANGER K y APPARATUS Fon INCINERATING MATERIAL Filed Aug; 19, 1936 Sept. 28, 1937.

mm wm Patented Sept. 28, 1937 UNITED STATES PATENT oFFlCE 1 Claim.

This invention relates to apparatus for incinerating material, such as sewage.

More specifically stated, the invention relates to apparatus for-disposing of sewage screenings and sludge cake. The disposal of such matter constitutes a very serious problem in large cities and involves an enormous expense. Sometimes such material is towed out to sea and dumped, thus polluting the coastal waters. It has been @proposed to convert the material into fertilizer, but this has been found to be too expensive Yto be practical.

The burning of sewage screenings and sludge cake presents unusual problems due to the relatively large water content even after a part of the water has been removed by vacuum filters and other means. 'Unless the temperatures in the various parts of the apparatus are properly regulated and controlled the outer layer of the "-material will be closed or sealed with the moisture confined therein. Furthermore, it has been found that for proper and eicient incineration the temperature at the receiving end of the apparatus should be relatively low and the mate- Jrial should be gradually fed through the apparatus Vand kept in motion, being subjected to increasing temperatures until it is" burned to ash.

.This invention has for one of itsfobjects to provide apparatus for so burning or incinerating 'l sewage screenings or like material that the final product will be in the formvof ash easily disposed of andno objectionable gases will be released to the atmosphere.-

Another object of the invention is to provide apparatus of the character described so designed that the hot exhaust gases canbe utilized to heat the air which enters the intake end ofthe apparatus into which'is fed the materialV to be incinerated.

apparatus of the character described so designed thatzthe noxious gases from the burning materialy or sewage ,will pass through the lower drum and be burned therein, any unburned gases pass- :fing outwardly through the stack.

Another object of the invention is to provide apparatus .of the character described, so constructed that means is .provided for removing residual ash from the gases passing out of the 3 stack.

Further objects of the invention .will appear from the following specification taken in connection with the drawing which lforms a part of this application, and in which Fig. 1 is a vertical sectionalelevation i11us Another object of the invention is to provide y trating apparatus constructed in accordance with theinvention;

Fig. 2 is a vertical sectional elevation taken substantially on line 2--2 and illustrating the outlet passages for the burned gases and the passages through whichthe intake air is conducted and preheated; and

Fig. 3 is a detail sectional View showingthe gas washer.

The invention briefly described consists of incinerating apparatus particularly designed for burning and disposing of sewage screenings and sludge cake. The apparatus comprises rupper and lower rotatable drums, the material'being conducted to the inlet end of the upper drum, through said drum, and thence into the inlet end of the lower drum and through the lower drum, the ash or residue dropping into an ash pit at the outlet end of the lower drum and the hot gases passingfrom the outlet end of the lower drum upwardly through passages which surround air inlet conduits or passages andthus heat the air which is fed into the inlet end of the upper drum.

Heating means, such as an oil burner, is provided at the inlet end of the lower drum and heats and burns the material which has been gradually raised in temperature during its passage through the upper drum. The two drums as shown are oppositely inclined relative to each other and lifts are provided to lift the material during the rotation of the drums and during the passage ofthe material therethrough so as to permit the air and hot gases to have access to the material and thus release the gases from the material being burned and cause a maximum amount thereof to be consumed.

Means is provided in connection with the stack to prevent fine ash from being discharged from the stack, this means comprising a gas washer.

Further details of the invention will appear from the following description.

In the particular embodiment of the invention illustrated in the drawing, the apparatus comprises apair of drums A and B which are supz ported at the ends on suitable rollers II). The upper drum is supported on frame work vIl and the lower drum on frames I2. The two drums are positively rotated by means of suitable driving mechanism consisting of motors I5 which-507A or pulleys All.

Aposited on a table or shelf 6i.

radially disposed bales or lifts 2l which cause the material passing through the drum to be lifted and dropped during its passage, thus breaking up the material and permitting the air and hot gases to permeate the material, dry and burn it.

The lower drum B is provided with a lining 22 of firebrick or other suitable heat insulating material.

The drumA is not submitted to as high temperatures as the drum B and therefore is not provided With a lining.

The outlet end of the drum A and the inlet end of the drum B are disposed in and communicate with a chamber 25. A ledge or inclined shelf 25 is formed in this chamber intermediate the upper and lower portions thereof and deflects the material discharged from the drum A into the inlet end of the drum B. The lower portion of the chamber 25 is provided with heating means, such as an oil burner 21, the blast or flame of this burner being directed into the inlet end of the drum B.

t the outlet end of the drum B the incinerator has formed therein an ash pit 28 and a conduit 2S which communicates with a stack 3i). A door 23 is provided in the ash pit 2B for removing the ashes. A gate 24 is provided for closing the passage into the pit when the door 23 is open.

Means is provided in the stack 3U for heating the intake air for the drum A and from the showing in Fig. 2 it will be noted that the stack has formed therein vertical passages 3| for the hot gases received from the drum B and also .'has formed therein passages 32 which are disposed in heat exchange relation to the passages 3|. The passages 32 have formed therein baffles 33 for deflecting the air which is forced therethrough by a fan 313 which discharges the air into :the passages 32 through a conduit 35.

The air passages 32 communicate with an intake conduit [it which conducts the preheated air to the inlet end of the drum A.

The material to be incinerat'ed, such for inf stance, as sewage screenings, is collected in a tank or drum T and is pumped therefrom by an injector R to a hopper H. The hopper discharges the material into a casing 45 in which is mounted an endless belt liti supported on hexagonal drums The right hand pulley 41 viewing Fig. l is driven in the following manner: Shaft d3 of the pulley 4.1 has mounted thereon a gear 59 which meshes with a gear 50 mounted on a shaft i. Gear 5t in turn meshes with a gear 52 mounted on a shaft 53 which is driven by a belt 54 which engages a pulley 55 mounted on the shaft 53 and a pulley 56 mounted on a shaft 51 of a motor M.

The belt t@ passes between upper and lower sets of presser rolls 58 and 59 which squeeze the material and remove a considerable portion of the water therefrom. It is desirable that sludge, before incineration, be passed through a vacuum lter prior to feeding the material to the incinerator, so that a portion of the water may be extracted therefrom.

The discharge end of the belt @E delivers the material to a chute 5i? through which it is de- Sludge cake from a vacuum filter may be fed into the chute 5l) by a conveyer lle.

A plunger 52 is slidably mounted on the table or support Si and is connected by a link 53 to a l-ever St mounted on a fixed pivot 65. The lever 64 is connected intermediate its ends at 66 to a link 61, the other end of which is connected to a crank arm 68 on a shaft 69 of a motor 10.

In order to prevent material being fed from the chute 66 when the plunger 62 is retracted, a stop plate 1| is connected to the shelf or table 6| and slides through slots in the chute B0 at the discharge end of the conduit or chute 60, closing the chute when the shelf 6l is retracted. The stop plate 1| thus acts as a slide valve. The plunger 62 acts as a pusher to feed the material along the table or support 6| and into the drum A.

In order to prevent fine ash from passing out through the stack a gas washer is provided, through which the gas can be by-passed. This construction is shown particularly in Fig. 3. The washer comprises a casing 15 having a chamber communicating with the stack 3B through inlet and outlet conduits '55 and 11. A water conduit 13 conducts water to the chamber and discharges the water through spray nozzles 19. Bales 80 are disposed below the nozzles and baffles 8| are disposed above the nozzles to intercept any ash or material in the outgoing gas. A fan 82 is mounted in the outlet conduit 11 and draws the gases through the chamber and forces it through the conduit 11 into the stack.

If desired, the amount of gas by-passed through the Washer can be regulated by a buttery Valve 85 mounted in the stack. If this Valve is closed all the gas will be drawn through the Washer.

The water and residue ash flows out of the chamber through an outlet pipe 86.

Operation The apparatus above described operates as follows: The material to be incinerated is fed into the receiving end of the drum A by the reciprocating feed table or shelf Bl and gradually passes from the receiving end to the discharge end of the drum A, which as shown in Fig. 1, is inclined downwardly from the receiving to the discharge ends thereof. Preheated air enters the drum A through the conduit 40, this air having been heated by the hot gases discharged from the drum B.

During its passage through the drum A the material is lifted and dropped and the hot air is permitted to permeate the material which is thus broken up and the moisture content is materially reduced.

From the drum A the material drops downwardly and is deflected by the shelf 26 into the inlet end of the drum B where it meets the hot blast of the oil burner 21 and is heated and burned during its passage from the inlet end to the discharge end of the drum B. During its passage through the drum B the material is also lifted and dropped and broken up, the gas being freed therefrom, a part of the gas being burned and the remainder passing outwardly through the passage 29 into thestack.

The ash resulting from the burned material drops into the ash pit 28 and can be Yremoved therefrom.

From the description in the preceding paragraphs it will be obvious that the draft or direction of flow of the hot air and gases in this apparatus is through the upper drumfrom the inlet to the outlet end thereof and through the lower drum from the inlet to the dischargeend thereof. Thus, the noxious gases from the sewage screenings or other material pass from the drum A into the drum B and in the drum B are burned to a large extent. Any unburned gases pass into the. stack.

The air fed to the upper drum A is preheated by the gases in the stack and this hot air heats and dries the material passing through the drum and materially reduces the moisture content.

Any ne ash passing into the stack is removed by the gas washer and the valve 85 can be adjusted to regulate the passage of gas through the washer.

From the foregoing specication it will be evident that a simple, practical and eicient incinerator has been designed and that by means of this apparatus a maximum quantity of material can be disposed of at a minimum cost.

Although one specic embodiment of the invention has been particularly shown and described, it will be understood that the invention is capable of modication and that changes in the construction and in the arrangement of the various cooperating parts may be made without departing from the spirit or scope of the invention, as expressed in the following claim.

What I claim is:

Apparatus of the character described comprising a pair of oppositely inclined rotatable drums disposed one above the other, means for rotating said drums, a chamber communicating with the outlet en-d of the upper drum and the inlet end of the lower drum,heating means at the inlet end of the lower drum arranged to direct a blast of heat on the material as it passes from the outlet end of the upper drum into the inlet end of the lower drum, a stack communicating with and disposed at the outlet end of the lower drum, means for conducting material to. the inlet end of the upper drum, means for conducting the material from the outlet end of the upper drum to the inlet end of the lower drum, and means located in heat exchange relation to said stack for conducting hot air to the inlet end of the upper drum.

ROGER GRANGER. 

